It’s fascinating stuff from beginning to end as you try to stay apace with a story that stretches from 2044 to 2074.

Add to that, time travel, which is always a tricky thing.

Not here though.

The premise relies on its plausibility in the shape of a young Joe (Gordon-Levitt), a kind of gun-for-hire by bosses in the future who send back criminals they want assassinated. Not as tough to get as it sounds but very clever.

The assassin/shooter stands on an empty lot next to a typical American crop field, a body drops from the sky at a designated time, hooded for convenience, and young Joe has to pop it, no questions asked, and dump the body.

Until unexpectedly, because these guys are from the future, you’re faced with your older self – and the fun begins.

Think of the turmoil. You have been doing this as routinely as feeding the dogs for a few years, but suddenly there’s something familiar about the body you’re expected to simply obliterate.

The questions start tumbling as the tension climbs and the pace picks up dramatically.

These days, thrillers are done so well on television (Homeland, 24, Damages) that filmmakers really have to come up with a novel story and then deliver the goods in full-screen splendour.

Cunningly, they have taken two actors here and set one up against the other.

In addition, one is playing the other’s younger self in real time. You better get that right, the mannerisms, the look, everything – and they do. Willis has always been a very deliberate actor which gives the young Gordon-Levitt something to grab hold of. And this makes it even more intriguing to watch.

These young men have to take out the so-called criminals from the future but are sent back in time to get them – literally – off the face of their Earth. These gunmen are called loopers, hence the title.

All that might sound just that bit too loopy, but it’s not. There’s a very good story that grabs you from the the word go. One that scratches around as much in the heart as in the mind. It’s not just run-of-the-mill action ramped up as a sassy story. You have to keep up with your racing heartbeat in the mental stakes, if you really want to reap the rewards.

It’s perfect to wrap you mind around at the end of the year when everyone seems to be tuning out.